scholarly journals New Approaches to Processing Ground-based SAR (GBSAR) Data for Deformation Monitoring

2018 ◽  
Vol 10 (12) ◽  
pp. 1936 ◽  
Author(s):  
Sichun Long ◽  
Aixia Tong ◽  
Ying Yuan ◽  
Zhenhong Li ◽  
Wenhao Wu ◽  
...  
Keyword(s):  
Signal To Noise Ratio ◽  
Atmospheric Correction ◽  
Deformation Monitoring ◽  
Atmospheric Effects ◽  
Threshold Optimization ◽  
Before And After ◽  
Multiple Threshold ◽  
The Stability ◽  
Average Coherence

In this paper, aiming at the limitation of persistence scatterers (PS) points selection, a new method for selecting PS points has been introduced based on the average coherence coefficient, amplitude dispersion index, estimated signal-to-noise ratio and displacement standard deviation of multiple threshold optimization. The stability and quality of this method are better than that of a single model. In addition, an atmospheric correction model has also been proposed to estimate the atmospheric effects on Ground-based synthetic aperture radar (GBSAR) observations. After comparing the monitoring results before and after correction, we clearly found that the results are in good agreement with the actual observations after applying the proposed atmospheric correction approach.

scholarly journals Sonar using chaotic sounding signals

2021 ◽  
pp. 36-40
Author(s):  
Ш.С. Фахми ◽  
С.В. Горяинов ◽  
А.В. Калач
Keyword(s):  
Signal To Noise Ratio ◽  
Water Environment ◽  
Deterministic Chaos ◽  
Reference Method ◽  
Current Approach ◽  
Arbitrary System ◽  
Simulated Environment ◽  
Before And After ◽  
Probing Signal ◽  
The Stability

В данной работе рассматривается подход к генерации зондирующего сигнала гидролокатора, основанный на применении систем с детерминированным хаосом. Рассматриваются актуальные подход к генерации зондирующего сигнала при проектировании гидролокаторов. Приводится описание полуявного метода Верле для произвольной системы обыкновенных дифференциальных уравнений. Приводится методология построения композиционных схем для получения методов численного интегрирования произвольного порядка на основе симметричного опорного метода. Приводятся результаты компьютерного моделирования форм различных сигналов до и после прохождения через имитацию водной среды. Приводятся экспериментальные результаты оценки погрешности в распознавании сигнала при различных значениях соотношения сигнал/шум имитируемой среды, проводится сравнительная оценка в значениях, полученных с использованием различных сигналов. Приводятся результаты оценки устойчивости исследуемых сигналов к перекрёстным помехам, проведена сравнительная оценка рассмотренных подходов к генерации зондирующего сигнала. Сделаны выводы о применимости хаотических сигналов в качестве зондирующих In this paper, we consider an approach to generating a sonar sounding signal based on the use of systems with deterministic chaos. The current approach to the generation of sounding singal in the design of sonar is considered. The semi-implicit Wehrle method for an arbitrary system of ordinary differential equations is described. A methodology for constructing composite schemes for obtaining methods of numerical integration of arbitrary order based on the symmetric reference method is presented. The results of computer simulation of the forms of various signals before and after passing through the simulated water environment are presented. Experimental results of estimating the error in signal recognition at different values of the signal-to-noise ratio of the simulated environment are presented, and a comparative assessment is made in the values obtained using different signals. The results of the evaluation of the stability of the studied signals to crosstalk are presented, and a comparative evaluation of the considered approaches to the generation of the probing signal is carried out. Conclusions are drawn about the applicability of chaotic signals as probing signals

scholarly journals FORMULASI SEDIAAN LOTION SARI KERING HERBA PEGAGAN (Centella asiatica(L.) URBAN ) DENGAN VARIASI KONSENTRASI EMULGATOR SPAN 60 DAN TWEEN 60

Media Farmasi ◽  
2020 ◽  
Vol 16 (1) ◽  
pp. 1
Author(s):  
Arisanty Arisanty ◽  
Santi Sinala ◽  
Muli Sukmawaty ◽  
Andi Masna
Keyword(s):  
Centella Asiatica ◽  
Physical Quality ◽  
Accelerated Storage ◽  
Before And After ◽  
Quality Stability ◽  
Dispersion Test ◽  
The Stability ◽  
Tween 60 ◽  
Span 60

Gotu Kola (Centella asiatica (L.) Urb) is a plant widely grown and scientifically proven to be an antioxidant. This study makes a lotion formula containing dried Gotu kola herb with varying concentrations of emulgator span 60 and tween 60. It determines the concentration of span 60 and tween 60, producing lotions with the most stable physical quality and accelerated storage methods. The lotion was prepared using a concentration of Centellaasiatica (L.) Herbaceous Dry Herb extract of 1% and an Emulgator span 60 and tween 60 in a concentration variation of 5%, 7.5%, and 10%. The stability of the lotion was determined based on quality observations. The physical condition before and after the storage is accelerated for six cycles at a temperature of 5oC and 35oC in organoleptic, homogeneous, pH, viscosity, diffusion power, and emulsion type. The research results show the physical quality stability of formula I (5% emulgator) did not meet the requirements of the dispersion test before storage was accelerated. In contrast, the formula with a 7.5% emulgator met the physical quality requirements of the preparation before and after storage was accelerated. Additionally, the 10% emulgator did not meet the requirements of the dispersion test after accelerated storage. The type of emulsion in all three formulas is the M / A type. The most stable physical quality of the three preparations is a formula with a 7.5% emulgator.Keywords: Lotion, Gotu kola (Centella asiatica (L.) Urb), physical quality, span, and tween.Pegagan (Centella asiatica(L.)Urb) merupakan tanaman yang banyak tumbuh di Indonesia dan telah terbukti secara ilmiah memiliki kemampuan sebagai antioksidan. Penelitian ini bertujuan  untuk membuat formula lotion yang  mengandung sari kering herba pegagan (Centella asiatica(L.) Urban) dengan variasi konsentrasi emulgator span 60 dan tween 60, dan untuk mengetahui konsetrasi span 60 dan tween 60 yang menghasilkan lotion dengan mutu fisik yang paling stabil dengan metode penyimpanan dipercepat. Sediaan dibuat lotion dengan konsentrasi sari Kering Herba  Pegagan (Centellaasiatica(L.) Urban ) sebesar 1% dan Emulgator span 60 serta tween 60 dengan variasi konsentrasi 5%, 7,5%, dan 10% kemudian stabilitas sedian lotion ditentukan berdasarkan pengamatan mutu fisik sebelum dans sesudah penyimpanan dipercepat selama 6 siklus pada suhu 5oCdan 35oC yang meliputi organeleptis, homogentias, pH, viskositas, daya sebar, dan tipe emulsi. Hasil penelitian pada pengujian kestabilan mutu fisik formula I (emulgator 5%) tidak memenuhi syarat pada uji daya sebar sebelum penyimpanan dipercepat, sedangkan Formula dengan emulgator 7,5% memenuhi persyaratan mutu fisik sediaan sebelum maupun sesudah penyimpanan dipercepat, dan formula dengan emulgator 10% tidak memenuhi syarat pada uji daya sebar setelah penyimpanan dipercepat, untuk tipe emulsi pada ketiga formula tersebut merupakan tipe emulsiM/A. Mutu fisik yang paling stabil dari ketiga sediaan tersebut adalah formula dengan emulgator 7,5%.Kata kunci : Lotion,  herba pegagan (Centella asiatica (L.) Urb), mutu fisik, span dan tween.

scholarly journals Changes in kinesiostabilogram parameters and movement speed of stroke patients while increasing their physical activity due to the use of biofeedback method

2021 ◽  
Author(s):  
Victoria Zaborova ◽  
Anatoly Fesyun ◽  
Konstantin Gurevich ◽  
Alevtina Oranskaya ◽  
Alexey Rylsky ◽  
...  
Keyword(s):  
Quality Of Life ◽  
Physical Activity ◽  
Depression Scale ◽  
Movement Speed ◽  
Stroke Survivors ◽  
Before And After ◽  
Web Camera ◽  
The Stability ◽  
Complications Of Stroke

Balance disorders are complications of stroke survivors. Aim of this study was the establish effectiveness of the biofeedback approach. In this intervention study 245 patients with early diagnosis of acute disturbance of cerebral circulation (ADCC) were examined. Patients able to move independently were treated by standard conservative ADCC therapy on an outpatient approach, but they continued to have problems with coordination of movement in upright position. Then they were submitted to an increasing physical activity based on five sessions of biofeedback, i.e., a complex rehabilitation of patients with motor pathology "Trust-M" according to TU 9442-001-63704475-2010. Mobility rates were assessed using a web camera. Patients' quality of life was evaluated by SF-36 questionnaire and the Hospital Anxiety and Depression Scale (HADS). All parameters were recorded before and after 5 sessions of biofeedback. After treatment, the stability indicators improved and all patients showed a significant increase in motion rate and quality of life. At the same time, the severity of pain and of depression and anxiety decreased. Negative correlations of average strength between the quadrant and patient HADS scaling rates were obtained. In conclusion, our work shows effectiveness of the biofeedback technique for correcting coordination in stroke survivors.

scholarly journals Determining the optical stability of printed laboratory substrates with wheat pulp after ageing treatment

2021 ◽  
Vol 30 (1) ◽  
pp. 15-24
Author(s):  
Valentina Radić Seleš ◽  
◽  
Irena Bates ◽  
Ivana Plazonić ◽  
Maja Rudolf ◽  
...  
Keyword(s):  
Test Chamber ◽  
Reflectance Spectra ◽  
Artificial Ageing ◽  
Ageing Treatment ◽  
Near Ultraviolet ◽  
Optical Stability ◽  
Before And After ◽  
The Stability ◽  
Board Industry

The use of recovered paper in the paper and board industry worldwide has increased in the last decade. The recycling process affects several properties of the paper, so recovered pulp needs to be enriched with a certain amount of virgin fibre to increase the strength and quality of the paper, and thus the quality of the print. Since the cellulose-based printing substrates are sensitive to photolytic damage caused by exposure to light and high temperature, the focus of the research was to evaluate the stability of digital UV inkjet prints on laboratory substrates with wheat pulp. Assessment of the optical stability of laboratory substrates and prints made on them after ageing treatment was based on the reflectance spectra measurements before and after artificial ageing. In order to observe the optical changes that occur in cellulose printing substrates, unprinted and digital printed substrates were placed in an artificial ageing equipment SunTEST XLS+ test chamber according to standard ASTM D 6789-02. The test chamber emits visible and near ultraviolet electromagnetic radiation in the range from 290 nm to 800 nm. With the deterioration of the optical stability of unprinted and digital printed substrates, it was observed through the reflectance spectra (R) and the Euclidean colour difference (ΔE00*) that the highest colour degradation of all analyzed samples, occurs in the first 48 hours of artificial ageing. The results of this analysis confirm that the addition of wheat pulp in paper pulp provides better optical stability of unprinted and digital printed laboratory substrates.

scholarly journals Atmospheric Correction Thresholds for Ground-Based Radar Interferometry Deformation Monitoring Estimated Using Time Series Analyses

2020 ◽  
Vol 12 (14) ◽  
pp. 2236 ◽  
Author(s):  
Tomasz Owerko ◽  
Przemysław Kuras ◽  
Łukasz Ortyl
Keyword(s):  
Time Series ◽  
Satellite Data ◽  
Time Series Data ◽  
Learning Algorithm ◽  
Atmospheric Correction ◽  
Deformation Monitoring ◽  
Radar Interferometry ◽  
Series Data ◽  
Atmospheric Conditions ◽  
The Stability

Ground-based radar interferometry (GBSAR) is a useful method to control the stability of engineering objects and elements of geographical spaces at risk of deformation or displacement. To secure accurate and credible measurement results, it is crucial to consider atmospheric conditions as they influence the corrections to distance measurements. These conditions are especially important considering the radar bandwidth used. Measurements for the stability of engineering objects are not always performed in locations where meteorological monitoring is prevalent; however, information about the range of variability in atmospheric corrections is always welcome. The authors present a hybrid method to estimate the probable need of atmospheric corrections, which allows partly eliminating false positive alarms of deformations as caused by atmospheric fluctuations. Unlike the numerous publications on atmospheric reductions focused on the current state of the atmosphere, the proposed solution is based on applying a classic machine learning algorithm designed for the SARIMAX (Seasonal Autoregressive Integrated Moving Average with covariate at time) time series data model for satellite data shared by NASA (National Aeronautics and Space Administration) during the Landsat MODIS (Moderate Resolution Imaging Spectroradiometer) mission before performing residual estimation during the monitoring phase. Example calculations (proof of concept) were made for ten-year satellite data covering a region for experimental flood bank stability observations as performed using the IBIS-L (Image by Interferometric Survey—Landslide) radar and for target monitoring data (ground measurements).

Least-squares decomposition with time–space constraint for denoising microseismic data

2020 ◽  
Vol 222 (3) ◽  
pp. 1864-1880
Author(s):  
Yangkang Chen ◽  
Wei Chen ◽  
Yufeng Wang ◽  
Min Bai
Keyword(s):  
Least Squares ◽  
Signal To Noise Ratio ◽  
Random Noise ◽  
Microseismic Data ◽  
Smoothness Constraint ◽  
Time Space ◽  
Wide Range ◽  
The Stability ◽  
And Inversion

SUMMARY Microseismic data are usually of low signal-to-noise ratio (SNR), which makes it difficult to utilize the microseismic waveforms for imaging and inversion. We develop a useful denoising algorithm based on a non-stationary least-squares decomposition model to enhance the quality of microseismic signals. The microseismic signals are assumed to be represented by a superposition of several smoothly variable components. We construct a least-squares inverse problem to solve for the the smooth components. We constrain the least-squares inversion via both time and space constraints. The temporal smoothness constraint is applied to ensure the stability when calculating the non-stationary autoregression coefficients. The space-smoothness constraint is applied to extract the spatial correlation among multichannel microseismic traces. The new algorithm is validated via several synthetic and real microseismic data and are proved to be effective. Comparison with the state-of-the-art algorithms demonstrates that the proposed method is more powerful in suppressing random noise of a wide range of levels than its competing methods.

scholarly journals The Working Conditions and Optimisation of a Large Rainwater Harvesting and Treatment System in an Area at a Risk of Erosion

2021 ◽  
Author(s):  
Tomasz Zubala
Keyword(s):  
Suspended Solids ◽  
Rainwater Harvesting ◽  
Wholesale Market ◽  
Building Collapse ◽  
Quality Of Water ◽  
Long Run ◽  
Before And After ◽  
Operational Errors ◽  
The Stability

AbstractRainwater harvesting and treatment systems (RHTS) are used in many places around the world as a part of sustainable water management. They decrease the risk of overloading the sewage network and environmental pollution. The efficiency and reasonableness of using such solutions in specific erosive conditions are not sufficiently understood. The aim of the study was to evaluate the operation of RHTS, receiving effluents from the wholesale market and fuel station (twenty years of observations). The studied system is located in an area endangered by water erosion. In the study period, due to the accumulation of erosive phenomena, it was necessary to optimise the system (including the installation of new devices and increasing the capacity of reservoirs). The analyses referred to the stability and work safety of the most important equipment and water treatment efficiency. The quality of water in the reservoirs was measured before and after the modernisation of the system. Selected physical, oxygen, biogenic and salinity indicators were determined in the water. During the study, RHTS had a positive effect on the quality of rainwater runoff – the values of many contaminants were reduced (RHTS 1: suspended solids, nitrogen, iron, potassium; RHTS 2: conductivity, suspended solids, nitrogen). Design and operational errors were noticed that in the long run may contribute to deteriorating the operational efficiency and even lead to a building collapse (intense erosive phenomena). This study clearly demonstrates that building a rainwater management system is a highly site-specific issue.

scholarly journals ATMOSPHERIC PHASE DELAY CORRECTION OF D-INSAR BASED ON SENTINEL-1A

2018 ◽  
Vol XLII-3 ◽  
pp. 955-960
Author(s):  
X. Li ◽  
G. Huang ◽  
Q. Kong
Keyword(s):  
Yellow River ◽  
Atmospheric Correction ◽  
Yellow River Delta ◽  
Phase Delay ◽  
Tropospheric Delay ◽  
Atmospheric Effects ◽  
Monitoring Accuracy ◽  
Before And After ◽  
Subsidence Monitoring ◽  
Delay Correction

In this paper, we used the Generic Atmospheric Correction Online Service for InSAR (GACOS) tropospheric delay maps to correct the atmospheric phase delay of the differential interferometric synthetic aperture radar (D-InSAR) monitoring, and we improved the accuracy of subsidence monitoring using D-InSAR technology. Atmospheric phase delay, as one of the most important errors that limit the monitoring accuracy of InSAR, would lead to the masking of true phase in subsidence monitoring. For the problem, this paper used the Sentinel-1A images and the tropospheric delay maps got from GACOS to monitor the subsidence of the Yellow River Delta in Shandong Province. The conventional D-InSAR processing was performed using the GAMMA software. The MATLAB codes were used to correct the atmospheric delay of the D-InSAR results. The results before and after the atmospheric phase delay correction were verified and analyzed in the main subsidence area. The experimental results show that atmospheric phase influences the deformation results to a certain extent. After the correction, the measurement error of vertical deformation is reduced by about 18 mm, which proves that the removal of atmospheric effects can improve the accuracy of the D-InSAR monitoring.

The stability of dislocation networks under various oxygen-doping conditions in superconducting Bi2Sr2CaCu2Oy single crystals and their influence on the flux pinning properties

1994 ◽  
Vol 52 ◽  
pp. 802-803
Author(s):  
Y. Feng ◽  
X. Y. Cai ◽  
R. J. Kelley ◽  
D. C. Larbalestier
Keyword(s):  
Single Crystals ◽  
Oxygen Content ◽  
Basal Plane ◽  
Flux Pinning ◽  
Pinning Centers ◽  
Before And After ◽  
Anomalous Peak ◽  
Basal Plane Dislocation ◽  
The Stability ◽  
Further Development

The issue of strong flux pinning is crucial to the further development of high critical current density Bi-Sr-Ca-Cu-O (BSCCO) superconductors in conductor-like applications, yet the pinning mechanisms are still much debated. Anomalous peaks in the M-H (magnetization vs. magnetic field) loops are commonly observed in Bi2Sr2CaCu2Oy (Bi-2212) single crystals. Oxygen vacancies may be effective flux pinning centers in BSCCO, as has been found in YBCO. However, it has also been proposed that basal-plane dislocation networks also act as effective pinning centers. Yang et al. proposed that the characteristic scale of the basal-plane dislocation networksmay strongly depend on oxygen content and the anomalous peak in the M-H loop at ˜20-30K may be due tothe flux pinning of decoupled two-dimensional pancake vortices by the dislocation networks. In light of this, we have performed an insitu observation on the dislocation networks precisely at the same region before and after annealing in air, vacuumand oxygen, in order to verify whether the dislocation networks change with varying oxygen content Inall cases, we have not found any noticeable changes in dislocation structure, regardless of the drastic changes in Tc and the anomalous magnetization. Therefore, it does not appear that the anomalous peak in the M-H loops is controlled by the basal-plane dislocation networks.

Sign in / Sign up

Export Citation Format

Share Document